Some progressives carry a must drop figure, a ceiling by which the jackpot is guaranteed to be won, which makes a pot close to its limit more likely to pay soon. Very large wins are often paid in instalments or after extra identity checks, and the terms say how. A jackpot that has not dropped for a long time is no more due than any other, unless a must drop ceiling is written into its rules.
Jackpots are won in one of two ways. Some need a specific combination, such as five jackpot symbols on a line at the maximum stake. Others are triggered at random after any spin, often through a jackpot wheel or a bonus game that picks one of several tiers. Random triggers usually give a larger stake a better chance of starting the jackpot game, a rule the game information states plainly in most titles.
Progressive jackpots differ by how widely they are shared. A standalone progressive grows from the stakes on a single game, a local one is shared by several games in one casino, and a network jackpot collects from the same games across many casinos at once. The wider the pool, the larger and rarer the top prize. The jackpot display usually names its type, and the game rules say which casinos or titles pay into it.